add display of app version in UI

.github/workflows/docker.yml

@@ -30,6 +30,9 @@ jobs:
     - name: Set up Docker Buildx
       uses: docker/setup-buildx-action@v2
 
+    - name: Create .version file
+      run: echo ${{ github.ref_name }} > .version
+
     - name: Login to Docker Hub
       uses: docker/login-action@v2
       with: